NiteIze makes a simple band with wide elastic loops of two sizes and velcro to fasten it on your head. It's not nearly as slick as 4seven's product, but can probably be had for $5-$10. It was originally intended for use with a MiniMag, so most any AA light will work fine. At the moment I can find mine, so I'm not sure if the loops will stretch enough for a P2D or a P3D, but I'd bet it would work. I found mine at an REI store, and they probably can be found at other camping stores. It works okay, but you have to readjust the band to change the angle of the light.
Geoff
Sorry to repeat your info, OCDGearhead. You beat me to it while I was typing.